You can, you just don't share the instance-local timeline. If you're mostly talking with people you follow and vice-versa, it all works pretty seamlessly. But p

You can, you just don't share the instance-local timeline. If you're mostly talking with people you follow and vice-versa, it all works pretty seamlessly. But people on other instances won't discover your posts via the local timeline, which is where a lot of people start when they first join. You might be visible in the global timeline depending, but that's a mess. :)